Attack on Titan(進撃の巨人Shingeki no Kyojin?, lit. "Advancing Giants") is a Japanese manga series written and illustrated by Hajime Isayama. The story centers around the lives of Eren Jaeger and his adoptive sister Mikasa Ackerman, who live in a world where the remnants of the human population live inside cities surrounded by enormous walls due to the sudden appearance of the Titans, gigantic humanoid creatures who devour humans seemingly without reason. Their lives are changed forever after the appearance of a colossal Titan brings about the destruction of their home and the death of their mother, spurring them to enter the army to battle the Titans themselves.